Hammer mill



July 5, 1938. w. H. PRESTON HAMMER MILL 4 Sheets-Sheet 2 Filed Feb. 17, 1936 %zls ATTORNEY.

July 5, 1938. w. H. PRESTON HAMMER MI'LL 4 Sheets-Sheet 3 1NVENT0R. sab CWM %'S ATTORNEY.

Filed Feb. 17, 1936 July 45, 1938. l w H. PRESTQN 2,122,658

HAMMERMILL Filed Feb. 17, 1936 4 Sheets-Sheet. 4

INVENTOR.

w10 292. www

%z5 ATTORNEY.

Patented July5, 1938 UNITED sTATEs PATENT OFFICE ward n. Shenmue, N'. Y., signor to Papec Machine Company, Shortsville, N. Y., a l corporation of New York Application February 1 Q6 Claims.

The present invention relates to hammer mills and has for its object to provideA a compact and simpliiled machine of this type 'whichcan be operated at a relatively low cost.

A further object of the invention is to' provide an improved machine for grinding dierent materials such, 4for example, as various kinds of cattle feed, the construction of the machine being such as to facilitate rapid and emcient handling of thev feed andthe grist or ground material, including improved means for conveying-the grist from its point of discharge by the grinding means to its destination with a minimum degree of frictional resistance. e

Atfurther object of the invention is to provide an improvedpfan and exhaust pipe arrangement for the ground material in combination with ifnproved means for discharging the material from the receiving chamber to the exhaust pipe `4in suspension to facilitate delivery of the same to its destination. I a

.A further object of the invention is to provide in a machine of. the present type, structural im- .provements by which to simplify and reduce the cost of constructing and operating the same and which also serve to increase its Aeiciency and reliability. Y

To these and other ends the invention resides in' certain improvements and. combinations of parts, all as will be hereinafter more fully described, thenovel features being pointed outy in the claims at the end of the specication. In. the drawings: Fig.,1 is a side elevation of a machine ing one form of the invention;

Fig. 2 is a plan view of the same parts broken away;

Fig. 3 is a'view in elevation of the lower portion of the machine shown in Fig. 1, with the outer section of the fan housing and other parts removed;

Fig. 4 is-a transverse sectional elevation taken substantially on -line 4-4 of Fig. 1;

Fig. 5 is a sectional elevation .taken substan tially on line 5-5 of Fig. '2; A 1

Fig. 6 is. a side elevation of a machine embodying a modied form 'of the invention:

embodywith certain Fig. 10 is a fragmentary transverse sectional elevation taken substantially on line IB-I of Fig. 9;

Fig. 1l is a perspective view of one end of the propeller supporting shaft and operating sleeve shown in Fig. 10, and

Fig. 12 is a fragmentarysectional elevation of sa modification corresponding generally to the type of propeller disposed within the grist receiv- 10 construction shown in Fig. 7, and having a worm ing chamber and an agitator within the suctionL conduit extending from said chamber.

The same reference numerals throughout the several views indicate the same parts'.

The present machine is designed to economi- 1'5 cally and efficiently grind or pulverize various lforms a grinding chamber II beneathwhichis a y lower chamber I2 into which the grist or pulverized/material is discharged, said lower chamber being formed between the side walls of the hous- 3Q' ing by a channel-shaped member I2a. The lower wall of. the chamber II comprises a substantially semi-circular separating screen I3. of any suitable mesh through which the ground material discharges to the receiving chamber I2, said 35 screen being suitably supported as, for example, by the curved angle'bars I4' secured on the side walls of the housing, Figs. 4 and 5, by any preferred means. A

In the upper portion of the housing is disposed 40 a curved retarding screen I5v of any suitable design and which holds the feed in the top of the housing until ground. The'feed' or other material to be ground or pulverized is, placed in a.l

` chute AI6 and discharged therefrom into the 45 Fig. 'I is a transverse section takensubstantially grinding chamber II through an opening I'l in the wall of the housing I0.

The grinding means is supported by a main shaft I8 extending transversely through the side walls of the housing and provided with a driving pulley I 8b, said shaft having thereon a suitable a `numberl of hammers comprising'the' arms or plates I9, which may or may not include the reversible grinding tips 20 on the opposite ends of the arms. In other words, the'hammers may 55 each be of a one-piece construction. Eowever, where it is founc desirable to use the removable tips they may be applied as shown or mounted loosely on or between the blades so as to be held by centrifugal force in a radial or tangential line from the blade-supporting shaft during operation thereof. The hammers when driven at4 high speed strike and grind or pulverize the material as it is fed to the screen from the chute through the opening |1. The pulverized material is discharged through the screen i3 to the receiving and collection chamber i2 from which it is discharged bymeans described hereinafter.

The hammer operating shaft I3 is carried by suitable bearings mounted within the casings or venclosures 2| `and 22, Fig. 4, suitably secured upon the side walls of the main housing I0 -oi' the machine. For supporting the bearing casing 22 the side wall lua of the housing is provided with outwardly offset portions 23 which are bent inwardly at 24 to receive the casing 22, which is held in position by a flanged ring 25 detachably connected with the offset wall porztions 23 by means of the bolts 26.

A centrifugal blower or suction fan 21 is xed on the hammer operating shaft i9, the rotary .element of the fan being enclosed within a suitable casing or housing comprising the inner and outer sections 2g and 29 which are anged to receive the bolts 30 by which the outer section is detachably connected with the inner section.

The inner section of the fan housing is con-l nected with and supp-arted by a channel-shaped conduit i3| secured upon the wall Illa of the main housing I0 by bolts 32, Fig. 4. 'I'he upper end of the channel member has an outwardly bent portion 33 of U-shaped construction Witt-dn which extends a correspondingly shaped outwardly bent portion 34 on the inner section 23 of the fan housing, said U-shapedpertlons being preferably connected one with another by' spot welding.- 'I'he lower portion of the fan housing section 28 is also connected with the channel member 3| '3y spot welding, preferably at or adjacent the point 35; Fig. 4.

The adjacent walls of the channel member3| and the inner section 28 of the fan housing are cut away to form an opening 36 which to establish communication between the fan housing and the ue or conduit 31 formed through cooperation of the channel member and the side wall |09 of the housing and into which the grist or ground material is discharged from the chamber |2 through an openinglgl38 in the wall |||a of the housing by means described hereinafter.

The grist receiving chamber |2 extends beneath the screen I3 and transversely of the axis of the hammer operating shaft I8, the outlet 38 being located preferably at a point between the ends of the chamber. A shaft 39 is extended longitudinally throughthe grist receiving chamber I2 and has its opposite ends j'ournaled` in bearings 4G- supported by th'e recessed or cup- Ashaped members 4| carried by opposite walls of by the revolving blade 45 on the shaft 39, which not only elects the grist well into the 'flue but .forces air therein under pressure sufficient to.

hc-id it in suspension whereby it may be more -aieaesa readily exhausted from the Eue by the opera.- tion of the fan. The blade is preferably secured between the laterally extending portions 49a of a collar 41a suitablysecured upon the screw carrying sleeve 42. Figs. 4 and 5.

The channel |2a is provided with a depressed portion |2b opposite the outlet 38A of the charnber i2, said depressed portion having side walls |2c between which the grist or ground material accumulating within said chamberis fed by the propellers 43 and 44 for ejection by the revolving blade 45 as stated above. The grist after entering the fan housing is discharged by the fan through the pipe 46 to the hopper'41, the latter having oppositely disposed bag receiving extensions 49 and 49 the outlets of which are cenhopper is supported by the vertically disposed rods 50, the upper ends of which are bent outwardly and suitably connected with the hopper. The rods are attached to the housing I0 by suitable upper and lower brackets 5| and 52, respectively, Fig. l.

'I'he flue 31 through which the grist is conveyed to the fan housing is provided at its lower end with a pocket 53 for the collection of any relatively heavy material or objects that may enter the grist chamber I2 and be discharged into the fiue from time to time, the removal of such objects from said pocket being` effected when desired through an opening 54 in the wall of the flue which is normally closed by aremovable door 55. A

It has heretofore been proposed to connect the grist receiving chamber in' the bottom of the housing for the grinding means with a fan or blower by a. relatively long bent or curved pipe projecting a considerable distance from the housing. '1111s .form of construction hasbeen found to be extremely objectionable for the reason that it not only interferes with the movements of those in charge of the machine and is likely to become bent or displaced, but also for the reason that its increased length and curvature greatly increases the frictional resistance offered to the passage of the grist therethrough. 'I'hese disadvantages have been overcome in the present machine by extending the flue or conduit upwardly between the housing for the grinding means and the fan onthe hammer shaft so that a relatively short and substantially straight vpassage is afforded between the fan housing and Vextent of the frictional resistance offered to the passage oi the grist to the fan as well as avoiding the use of a pipe or conduit protruding or projecting outwardly beyond the fan housing.

The propeller shaft 39 is provided with a pulley 56 driven by a beit 51 on a pulley 53 carried by a shaft 53 located outside of the housing I0 and paralleling the hammer shaft I3., The shaft 59 is provided with a pulley 50 driven by a beltt operated by a pulley 62 on the' hammerushaft I8, Figs. 1 and 5. A guard 63 is provided for the belt andthe pulleys 60 and 52, as shown in Figs. l

'I'he modification shown in Figs. 6, 7, and 8 is generally similar to that shown in Figs. l to' 5, inclusive, except for the construction of the propeller in the grist receiving chamber beneath the grinding chamber, and certain other forirs of the construction whichQhave been siightly modified. 'I'he housing |||b of the modiiied'form of the in- 'is l sections which form the grinding chamber Ila and the grist receiving chamber I2d therebeneath. ."Ihe lower wall of the chamber Ila comprises a substantially semi-circular screen |3a of any suitable mesh through which the grist or ground material discharges to the chamber i2d, the latter having a bottom wall l2e, the opposite ends of which are inclined to the horizontal, as shown in Fig. 8, so as to discharge the grist received thereby to the bottom of the chamber for ejection therefrom by means described hereinafter. Within the upper section of the housing is disposed a curved retarding screen lia similar to the screen I5 of Figs. 4 and 5, and provided v for the same purpose.

'I'he grinding means is supported by a. main edgewise projecting steel grinding tips 20a which operate to grind and pulverize the material as it is fed to the upper portion of the chamber Ila through a chute Ilia, suitably connected with the upper section of the housing. The chute and upper housing section constitute a'unit which is pivotally connected with the lower section of the housing at IIb so that said unit maybe swung to a position at which the hammers may be rendered accessible for repair and reversal of the tips. However, the hinged upper section of the housing is normally held in closed position by a clamping bolt I3b, the opposite ends of which are connected with the brackets i3c and i3d of the upper and lower housing sections, respective- 1y,assh wninFig. 6.

The h mmer operating shaft I3a is carried by suitable bearings Zia supported by brackets 22a xed on the walls of the housing I0b, preferably by spot welding.

The suction fan or centrifugal blower is mountcorresponding to those shown in Fig. 4, and have therefore been giventhe .same reference characters. The inner section 28 of the fan housing is connected With'and supported by a conduit or channel 3ia which has at its upper end a part formed to flt the U-shaped portion 34 of the inner section of the fan housing and with which it is suitably connected'by spot welding, or otherwise, as preferred.

The lower portion of the conduit 3Ia is connected with the Wall lllc of the hammer housing at 32a, by spot welding or otherwise. The outer wall of 'the conduit has its lower end resting upon a. flange Ilid of the housing and may be secured thereto by any suitable means, said outer wall being also suitably connected at 35a with the fan housing section 23.

The adjacent walls of the conduit 3Ia and the inner section of the fan housing are cutaway to afford an opening 36a for the passage of the grist from the conduit to the interior of the fan housing, thelower end of the conduit being also cut away to form an inlet for receiving the grist discharging from the chamber |2d through ythe outlet 38a of said chamber. I l

The means for ejecting the grist from the chamber I2d into the conduit 3Ia is in the form of a propeller which includes a rotatably mounted sleeve 64 paralleling the hammer shaft i8a andv are inclined relative to theaxis of the sleeve and serve to feed the grist from the chamber I2d, but at the 'same time allowing slippage when the blower is operating slowly either during starting or stopping or in cases where the flow of the material throughvthe flue may for any reason be interrupted.

The sleeve is provided with spaced bearings 66 at its opposite ends which are rotatably mounted 4 on a shaft 61 supported at one end by a bracket support suitably connected with the wall of.

the housing ib.' 'Ihe opposite ends of the shaft are cut away ,to form substantially semi-circular supporting parts 1I which are positioned in correspondingly shaped openings formed in the brackets 68 and 69 whereby the shaft is held against turning.

The space between the shaft and the sleeve 64 is preferably lled with a suitable lubricant, such as oil or grease, indicated at 12 whereby to vlubricate the bearings 66 of the sleeve, said bearings serving to seal the ends, of the sleeve and to prevent escape of the lubrication therefrom.

The conduit 31a is provided at its lower end witha pocket 13 for receiving any relatively heavy materials or objects which may be discharged to the grist receiving chamber 12d and be fed therefrom by the propeller blades 65 into said conduit. Removal of such objects from the pocket can readily be effected from time to time through an opening 14 in the outer wall of the conduit which is normally closed by a removable door 15 having a latch 16 rotatable to and from locking engagement -with the wall of the conduit by a handle 11 1rigidly connected with a supporting pivot member 18 for the latch which extends through the door as shown in Fig. 10.

The grist or ground material fed to the conl duit 3Ia from the receiving chamber I2d by rotation of the propeller blades therein is sucked up through the conduit into the fan housing by rotation of the fan Within the housing. The grist is discharged by the fan through the pipe 46 to the hopper 41 for alternate discharge to the feed bags through the extensions 48 and 49 of the hopper as described above in connection with Figs. l and 2 of the drawings. The discharge pipe 46, hopper 41, and its outlet extensions and thesupporting means for the hopper being the same in Fig. 6 as in Fig. 1, have been given the same reference characters.

'I'he driving means for the propeller sleeve 64 comprises a pulley 19 secured to the reduced end 64a of the sleeve and driven by a belt Bil which in turn is driven by a pulley 8l on the hammer shaft I8a. as shown in Fig. '7. 'I'he sleeve 64 is provided with a thrust bearing 82 interposed between the pulley 19 and the bracket supporting member 10 as shown in Fig. 10. The belt 86 is protected by a shield or cover plate 83 which forms a continuation of the channel-shaped bracket support 10, the lower edge of the cover, plate having one or more inwardly offset parts 34 engaging the rear face of the support 10 to maintain the cover in position thereon.

In the operation of the modification shown in Figs. l to 5, inclusive, the feed, such as grain and various kinds of roughage,'is discharged to the grinding chamber by the chute i6 and is driven against the retarding screen i5 and ground by the rotating hammers. The grist is discharged through the separating screen i3 into the elongated chamber l2 extending transversely of the hammer shaft. The oppositely pitched screw propellers 43-and 44 serve as means for feeding the grist or ground material fromrthe ends of said chamber to a point opposite the outlet 38, through which the material is discharged into the conduit 31 bythe rotating blade 45 which acts 'as a means for propelling the material :into said vconduit and for producing pressure therein to hold the material in suspension whereby exhaustion of the material from the conduit by the fan is greatly facilitated. 'I'he fan `operates to discharge thegrist through Lthe outlet pipe 46 to shaft, and the revolving blades 8.5 within said chamber allow slippage when the blower is operating slowly during starting or stopping. In

leach modication any relatively heavy materials or objects' discharged from the grist receiving chamber will' accumulate within the pocket formed at the bottom of the exhaust conduit and can be .removed from said pocket through the door thereof from time to time.

In the modlcation shown in Fig. 12 'the various parts ofthe machine will be the same as those shown in Figs. 6 to 11, inclusive, with the .exception Aof the propeller for discharging the` grist or ground'material from the receiving chamber 12d into'the conduit 31a, and the means for agitating and forcing the material upwardly within the conduit. Consequently'the parts of Fig. 12, which are the same as those for example of Fig. 7, are designatedby the same reference characters. 4 x

In Fig. 12 the .rotary sleeve A64 and the pulley and belt for driving the same are mounted and supported as in Figs. 7 and 10, but instead of employing the spaced blades 65.to discharge the grist from the chamber I Td, a worm is employed for this purpose which may be secured on the sleeve by any suitable-means. It will be understood that the worm type of propeller shown in Fig, 12 is particularly adapted for use whered it is desired to grindwet materials of various. kinds such forexample as wet fodder, hay, and the like, it being more ,difficult to effect discharge cf the material in this condition than when dry. The worm propeller will, of course, insure a more positive feed of the wet material from the grist receiving chamber into the bottom of the conduit Sla than the spacedv blades shown in Fig. 7. Furthermore, Withdrawal of the wet material from the conduit Bla. by suction produced by the operation ofthe fan cannot be effected as readily\ as in the case of dry material, in view of whichf fact an agitator or impeller has been mounted on the rotary sleeve 64 within'the conduit 3Ia comprising 'a hub-like. portion 86 suitably secured on said sleeve and having oppositely extending blades 81 which servev to force-the ground material upwardlywithin the conduit with a tend-l ency to maintain it in suspension therein to facilitate its withdrawal therefrom by the fan.

It will be understood that the `operation. of the impeller within the conduit will not interfere with the accumulation of the relatively heavy material or objects withinthe pocket 13 at the bottom of the conduit.V It will k-be further understood that in the modification shown in Fig. 12 that the unit comprising the pulley 19, sleeve 64, shaft 61, and associated parts, will be constructed,

mounted, and operated in the same manner as 5 the corresponding parts of Fig. 10, and that such units, with the Worm propeller 85 and agitator 86, 81 thereon can be kept o n hand and substituted for the grist propelling type of unit shown in Figs. 7 and 10 when desired. -1

y It will be understood that the machine of the present invention is adapted for grinding various other materials not specifically mentioned herein, in a highly satisfactory and economical manner. 1 One of the several advantages of the present invention is the Vertical and direct conduit connection between the grist receiving chamber and the fan housing, which permits the ground material to be lifted by the fan with much greater 20 and having an outlet intermediate its ends, a fan on said shaft, asubstantially vertical conduit ex- 3 tending between a wall of the housing and the fan and connecting said outlet with the fan housing, means rotatable Within said receiving chambei' about an axis transverse to the axisfof said shaft and operable toY advancefthe ground ma- 4 terial from the ends of trg; chamber to and through said outlet into said conduit, said fan operating to exhaust the ground material from said conduit, said conduit being extended below the outlet of said receiving chamber and form- 4 ing a pocket for the reception of the relatively heavy particles discharging from thechamber into the conduit, said conduit being provided'with an opening in its lower end adjacent said pocket and having a closure therefor, and driving means 5 for said last mentioned means.

2. In a grinding machine, a housing having a grinding chamber, grinding means within said chamber, an operating shaft for the grinding mea-ns extending from the housing at one side 55 thereof, a centrifugal bloweri on said shaft, an elongated receiving chamber for the ground material disposed beneath'said grinding chamber, said receiving chamber having an loutlet intermediate its ends, a conduit extending upwardly 6 adjacent a wall of the housing and forming a connecting passage between the fan and said outlet, a rotary element within said receiving `chamberextending transversely of said operatingV shaft and including means for advancing the C.

the housing at one sidethereof, a fan on said 7,5

shaft including a casing spaced from the housing, a receiving chamber for the ground material disposed beneath said grinding chamber and having an outlet disposed substantially midway between its ends, a conduit extending upwardly from the receiving chamber between the casing and the housing and discharging to said casing through the inner wall4 thereof, and means Within the receiving chamberfor discharging the ground material therefrom into said conduit, said means including parts for moving the material from the opposite ends of said chamber toward said outlet.

4. In a grinding machine, a housing having a grinding chamber, grinding means rotatable Within said chamber and provided with driving means, a receiving chamber for the ground material disposed below and communicating with the grinding chamber and having an outlet intermediate its ends, means rotatablewithin said chamber about an laxis substantially at right angles to the axis of rotation of said driving means and operable to nove the ground material from the ends of said chamber to and through said outlet, a fan connected with said driving means for operation thereby and including a casing spaced from the housing, vmeans extending between the housing and said casing and forming supporting means for the latter, and a. substantially straight discharge conduit for the ground material extending from said outlet upwardly between the housing and the fan casing and forming additional supporting means for the latter.

5. In a grinding machine, a housing having a grinding chamber, grinding means within said chamber provided with driving means, a receiving chamber for the ground material disposed below and communicating with the grinding chamber and having an outlet intermediate its ends, a rotary element within said receiving chamber having spaced helical members thereon for advancing the ground material from the ends of said receiving chamber toward said outlet, said rotary element also having a radial blade substantially parallel to the axis of said rotary element and extending between said helical members and opposite said outlet for discharging the ground material therethrough, a fan at one side of said housing including a casing, said fan being connected with said driving means for operation thereby, and a conduit extending between said casing andsaid outlet and forming a substantially straight discharge passage between the outlet and said casing.

6. In a grinding machine, a housing having a grinding chamber, grinding means within. said chamber provided with a driving element, a receiving chamber for the ground material disposed below and communicating with said grinding chamber and having an outlet intermediate its ends, a fan spaced from said housing and connected with said driving element for operation thereby, a substantially straight discharge conduit extending from a point below said outlet upwardly between the housing and the fan and forming a support for the latter, an impeller within the receiving chamber for moving the ground material from the ends thereof to and through the outlet into said conduit, means within said conduit adjacent the lower end thereof forl elevating the ground material within the conduit, said means being connected with the impeller for operation thereby, the lower end of said conduit forming a pocket for the reception of relatively heavy particles discharging from said chamber into thev conduit, said conduit having an outlet adjacent said pocket, and a removable closure for said outlet.

WARD H. PRESTON. 

